The head of the Virgin empire was alleged to have "directly" phoned David Parsley, then of the Sunday Express, on August 6 2004 "saying that British Airways were going to increase their surcharge".

Clare Montgomery, QC, making opening remarks for the defence in the trial of four BA executives, said Sir Richard and Virgin Atlantic's former corporate affairs chief Paul Moore had "used journalists to get information".

Having taken Sir Richard's call, Mr Parsley rang one of the defendants – BA's former media head Iain Burns – and learned that BA planned to increase its one-way surcharge from £2.50 to at least £6. Mr Parsely wrote the story prior to both carriers raising surcharges to £6 on August 9.

Ms Montgomery told jurors it was in such a context that they must consider a phone call, also on August 6, between Mr Burns and Mr Moore. "The reason why Burns was willing to give information to Moore was that he had already given it to the Express," she said.

Mr Burns stands accused alongside Andrew Crawley, BA's head of sales, Martin George, its former commercial director, and Alan Burnett, the airline's former head of UK and Ireland sales, of an alleged cartel offence under the 2002 Enterprise Act. It is said to have occurred between July 1 2004 and April 20 2006. All four deny the charges.

The Office of Fair Trading alleges that the four dishonestly colluded to fix the price of fuel surcharges with three Virgin Atlantic executives – its chief executive Steve Ridgway, former commercial chief William Boulter and Mr Moore.

Ms Montgomery, who is defending Mr George, explained to Southwark Crown Court that the Virgin officials were immune from prosecution and the company had escaped all fines because it blew the whistle on the alleged offence.

"If you want to get away with it, you've got to get in and confess," she said, adding that the financial value of immunity to Virgin "ran into the hundreds of millions of dollars".

She said the entire case was triggered by a "passing comment" from Mr Boulter that Mr Moore had spoken about fuel surcharges with someone at BA. After that, she said, Virgin was in "a race to get to the authorities first" and confess.

She asked the jury – the first to try any defendants on such a charge – to consider whether the BA four had made a "wicked attempt to fleece customers". This required, she said, proof that they had formed an agreement with Virgin, that "the intended operation of that agreement was to fix prices" and that "any person making that agreement did so dishonestly".

Ms Montgomery stressed that the fuel surcharge was only one part of the ticket price. "If the evidence shows that each airline intended to carry on fighting fiercely for every passenger... you may contend that this severely undermines" allegations of price-fixing, she said.